package utils;

import javax.imageio.ImageIO;
import java.awt.*; 
import java.awt.geom.AffineTransform; 
import java.awt.image.BufferedImage; 
import java.io.*; 
import java.util.Arrays; 
import java.util.Random; 
/**
* 生成验证码工具类 
*/ 
public class VerifyCodeUtil { 
public static final String VERIFY_CODES = 
"123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"; //不要0，避免与O混淆 
private static Random random = new Random(); 
/**
* 输出随机验证码图片流,并返回验证码值（一般传入输出流，响应response页面端，Web项目用的 
较多）
*
* @param w 
* @param h 
* @param os 
* @param verifySize 验证码长度 
* @return 
* @throws IOException 
*/ 
public static String outputVerifyImage(int w, int h, OutputStream os, int 
verifySize) throws IOException { 
String verifyCode = generateVerifyCode(verifySize); 
outputImage(w, h, os, verifyCode); 
return verifyCode; 
}
public static String generateVerifyCode(int verifySize) { 

    return generateVerifyCode(verifySize, VERIFY_CODES);
}
/**
* 使用指定源生成验证码 
*
* @param verifySize 验证码长度 
* @param sources 验证码字符源 
* @return 
*/ 
public static String generateVerifyCode(int verifySize, String sources) { 
// 未设定展示源的字码，赋默认值大写字母+数字 
if (sources == null || sources.length() == 0) { 
sources = VERIFY_CODES; 
}
int codesLen = sources.length(); 
Random rand = new Random(System.currentTimeMillis()); 
StringBuilder verifyCode = new StringBuilder(verifySize); 
for (int i = 0; i < verifySize; i++) { 
verifyCode.append(sources.charAt(rand.nextInt(codesLen - 1))); 
}
return verifyCode.toString(); 
}
/**
* 生成随机验证码文件,并返回验证码值 (生成本地图片文件形式，用的较少) 
*
* @param w 
* @param h 
* @param outputFile 
* @param verifySize 
* @return 
* @throws IOException 
*/ 
public static String outputVerifyImage(int w, int h, File outputFile, int 
verifySize) throws IOException { 
String verifyCode = generateVerifyCode(verifySize); 
outputImage(w, h, outputFile, verifyCode); 
return verifyCode; 
}

//    public static void main(String[] args) throws IOException {
//        File file = new File("D:/aaa.jpg");
//        VerifyCodeUtil.outputVerifyImage(100,40,file,4);
//    }
/**
* 生成指定验证码图像文件 
*
* @param w 
* @param h 
* @param outputFile 
* @param code 
* @throws IOException 
*/ 
public static void outputImage(int w, int h, File outputFile, String code)
throws IOException {
if (outputFile == null) { 
return; 
}
File dir = outputFile.getParentFile(); 
//文件不存在 
if (!dir.exists()) { 
//创建 
dir.mkdirs(); 
}
try {
outputFile.createNewFile(); 
FileOutputStream fos = new FileOutputStream(outputFile); 
outputImage(w, h, fos, code); 
fos.close(); 
} catch (IOException e) { 
throw e; 
} 
}
/**
* 输出指定验证码图片流 
*
* @param w 
* @param h 
* @param os 
* @param code 
* @throws IOException 
*/ 
public static void outputImage(int w, int h, OutputStream os, String code) 
throws IOException { 
int verifySize = code.length(); 
BufferedImage image = new BufferedImage(w, h, 
BufferedImage.TYPE_INT_RGB); 
Random rand = new Random(); 
Graphics2D g2 = image.createGraphics(); 
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, 
RenderingHints.VALUE_ANTIALIAS_ON); 
// 创建颜色集合，使用java.awt包下的类 
Color[] colors = new Color[5]; 
Color[] colorSpaces = new Color[]{Color.WHITE, Color.CYAN, 
Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA, Color.ORANGE, 
Color.PINK, Color.YELLOW}; 
float[] fractions = new float[colors.length]; 
for (int i = 0; i < colors.length; i++) { 
colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)]; 
fractions[i] = rand.nextFloat(); 
}
Arrays.sort(fractions); 
// 设置边框色 
g2.setColor(Color.GRAY); 
g2.fillRect(0, 0, w, h); 
Color c = getRandColor(200, 250); 
// 设置背景色 
g2.setColor(c); 
g2.fillRect(0, 2, w, h - 4);
// 绘制干扰线 
Random random = new Random(); 
// 设置线条的颜色 
g2.setColor(getRandColor(160, 200)); 
for (int i = 0; i < 20; i++) { 
int x = random.nextInt(w - 1); 
int y = random.nextInt(h - 1); 
int xl = random.nextInt(6) + 1; 
int yl = random.nextInt(12) + 1; 
g2.drawLine(x, y, x + xl + 40, y + yl + 20); 
}
// 添加噪点 
// 噪声率 
float yawpRate = 0.05f; 
int area = (int) (yawpRate * w * h); 
for (int i = 0; i < area; i++) { 
int x = random.nextInt(w); 
int y = random.nextInt(h); 
// 获取随机颜色 
int rgb = getRandomIntColor(); 
image.setRGB(x, y, rgb); 
}
// 添加图片扭曲 
shear(g2, w, h, c); 
//文字颜色 
g2.setColor(getRandColor(120, 160)); 
int fontSize = h - 4; 
Font font = new Font("Algerian", Font.ITALIC, fontSize); 
g2.setFont(font); 
char[] chars = code.toCharArray(); 
for (int i = 0; i < verifySize; i++) { 
AffineTransform affine = new AffineTransform(); 
affine.setToRotation(Math.PI / 4 * rand.nextDouble() * 
(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize / 2, h / 2); 
g2.setTransform(affine); 
g2.drawChars(chars, i, 1, ((w - 10) / verifySize) * i + 5, h / 2 + 
fontSize / 2 - 10); 
}
g2.dispose(); 
ImageIO.write(image, "png", os); 
}
/**
* 随机颜色 
*
* @param fc 
* @param bc 
* @return 
*/ 
private static Color getRandColor(int fc, int bc) { 
if (fc > 255) { 
fc = 255; 
}
if (bc > 255) { 
bc = 255;
}
int r = fc + random.nextInt(bc - fc); 
int g = fc + random.nextInt(bc - fc); 
int b = fc + random.nextInt(bc - fc); 
return new Color(r, g, b); 
}
private static int getRandomIntColor() { 
int[] rgb = getRandomRgb(); 
int color = 0; 
for (int c : rgb) { 
color = color << 8; 
color = color | c; 
}
return color; 
}
private static int[] getRandomRgb() { 
int[] rgb = new int[3]; 
for (int i = 0; i < 3; i++) { 
rgb[i] = random.nextInt(255); 
}
return rgb; 
}
private static void shear(Graphics g, int w1, int h1, Color color) { 
shearX(g, w1, h1, color); 
shearY(g, w1, h1, color); 
}
private static void shearX(Graphics g, int w1, int h1, Color color) { 
int period = random.nextInt(2); 
boolean borderGap = true; 
int frames = 1; 
int phase = random.nextInt(2); 
for (int i = 0; i < h1; i++) { 
double d = (double) (period >> 1) 
* Math.sin((double) i / (double) period 
+ (6.2831853071795862D * (double) phase) 
/ (double) frames); 
g.copyArea(0, i, w1, 1, (int) d, 0); 
if (borderGap) { 
g.setColor(color); 
g.drawLine((int) d, i, 0, i); 
g.drawLine((int) d + w1, i, w1, i); 
} 
} 
}
private static void shearY(Graphics g, int w1, int h1, Color color) { 
int period = random.nextInt(40) + 10; // 50; 
boolean borderGap = true;
int frames = 20; 
int phase = 7; 
for (int i = 0; i < w1; i++) { 
double d = (double) (period >> 1) 
* Math.sin((double) i / (double) period 
+ (6.2831853071795862D * (double) phase) 
/ (double) frames); 
g.copyArea(i, 0, 1, h1, 0, (int) d); 
if (borderGap) { 
g.setColor(color); 
g.drawLine(i, (int) d, i, 0); 
g.drawLine(i, (int) d + h1, i, h1); 
} 
} 
} 
}
